1. Field of the Invention
The invention relates to a protective bumper assembly for a refrigeration unit of the type adapted to be mounted on the front wall of a trailer. More specifically, it relates to such a bumper assembly which protects both the front and sides of such a refrigeration unit and which transmits force from the bumper to the front wall of the trailer.
2. Description of the Prior Art
Refrigeration units adapted to be mounted to the front end of the trailer of a tractor trailer vehicle for controlling the temperature within the trailer are well known in the art. It is common practice for such refrigerated trailers to be stored in a rail yard, or the like, without the tractor unit attached thereto. It is also common practice for such refrigerated trailers to be shipped by rail without the trailers attached thereto. During such storage or transportation of the trailer without the tractor attached, the refrigeration unit is subject to damage as a result of impact with other trailers and the refrigeration units of other trailers.
Various protective bumpers and bumper systems have been used with such units for the purpose of attempting to prevent or minimize damage to the refrigeration units. Known bumper systems have either been not robust enough to prevent damage or they transmitted the force of the collision into the frame of the refrigeration unit, thus, causing the frame to distort and causing internal unit damage.
A U.S. patent application entitled "Protective Bumper For A Transport Refrigeration Unit" filed on Feb. 20, 1998, as U.S. Ser. No. 09/027,386 and assigned to the Assignee of the present invention discloses a protective bumper assembly for a refrigeration unit of this type, which will protect the unit without the possibility of causing damage to the internal framework of the unit. The protective bumper assembly disclosed in this patent application is relatively inexpensive and can protect both the top and bottom of the refrigeration unit.
It has been found that the protective bumpers disclosed in the above-referenced patent application perform very well in protecting refrigeration units under the circumstances set forth above, but that they required additional protection in the corners of the unit. Such additional protection would protect the microprocessor and other components located on the left or right front sides of the covers of such units from damage when one trailer backed into another and the pointed rear corner of the trailer impacted a very narrow area in the corner of the unit, which the main bumpers did not protect.